The present invention relates to a fluid coupler for making a leakage-free connection between fluid-filled pipes and containers and, in particular, to a coupler employing two half-couplers each including a switchable valve and an adjusting means for opening and closing the valve.
Fluid couplers are used to establish a flow connection between two tubes or vessels which are filled, for example, with ink. The devices to be connected, such as hose ends, must be coupled together reliably, and the manipulations involved in the coupling process must be performable by relatively unskilled personnel. Further, the fluid medium must not be permitted to escape nor must air from the atmosphere enter into the connection point or into the interiors of the tubes or vessels. In addition, it is desirable that such device be usable for hydraulic as well as pneumatic systems.
German Pat. No. 2,416,836 discloses a device which achieves coupling and securing by the use of connecting tubes, each connecting tube being kept closed by a deformable closing, or blocking, member. When the connecting tubes are brought together, the closing member of each tube is displaced by rigid abutments disposed at the other tube. This produces a flow passage in each connecting tube through which the fluid can flow, the flow passage being produced during the connection of the tubes and no means being provided for closing the flow passage while the connecting tubes are coupled together.
U.S. Pat. No. 4,330,010 to Drescher et al. discloses a device which includes two coupling tubes in communication with the interiors of respective enclosures, each provided with a controllable closing member. The tubes are arrestable against one another in a position to establish a leakage-free connection between their flow passages. The formation and closing of the flow gap is effected by an adjusting means actuated by movement of a handle. However, this manipulation requires a certain skill on the part of the operator and the coupler is rather expensive to manufacture.
It is an object of the present invention to provide a coupling for the leakage-free connection of pipes and containers filled with a gas or other fluid which is simple in design, easy to handle, reliably prevents the medium from escaping and which prevents the entry of air into the filled pipes and containers.